2. Immunity - Notes taken from the lecture of Sir Joseph Joy Banzon, RMT PDF

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IMMUNOOGY & SEROLOGY IMMUNITY IMMUNOLOGY - the study of a host’s reactions when foreign substances are introduced into the body IMMUNITY - the state of being resistant to infection - all those physiological mechanisms that endow the animal with the capacity to recognize materials as ...

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IMMUNOOGY & SEROLOGY

IMMUNITY IMMUNOLOGY - the study of a host’s reactions when foreign substances are introduced into the body IMMUNITY - the state of being resistant to infection - all those physiological mechanisms that endow the animal with the capacity to recognize materials as foreign to itself & to neutralize, eliminate, or metabolize them with or without injury to its own tissue - complex reaction involving any different cells, molecules, & genes aimed essentially in maintaining the genetic integrity of an individual, protecting it from invasion of substances that can bear the imprint of a foreign genetic code - the body’s ability to resist foreign organisms & toxins (poisons) that damage tissues & organs TYPES OF IMMUNITY NATURAL IMMUNITY

ADAPTIVE IMMUNITY

1. Mechanisms involved are non-specific 2. Mechanisms that pre-exist the invasion of foreign agents 3. Components are pre-formed 4. They are non-adaptive, has a standardized magnitude of response 5. Lacks immunologic memory I.

1. Reinforcement 2. Inducibility 3. Specificity 4. Diversity 5. Memory 6. Specialization 7. Self-limitation 8. Discrimination

NATURAL / INNATE IMMUNITY (NON-SPECIFIC / NON-ADAPTIVE) - present since birth - ability of an individual to resist infections by means of normally present body functions - has standardized response to all invading antigen (no memory cells) TWO KINDS OF NATURAL / INNATE IMMUNITY: 1. EXTERNAL DEFENSE MECHANISM - structural barriers that prevents the penetration of microorganisms in the body a. PHYSICAL BARRIERS  Intact skin  Mucous membranes of Respiratory, GI, & GU tract  Ciliated Epithelium  Lacrimal Apparatus  Sweat & Sebaceous glands b. MECHANICAL BARRIERS  Peristaltic movement of intestine  Shedding of cells  Coughing & sneezing  Flushing action of urine c. CHEMICAL BARRIERS  Acidic pH: lactic acids & fatty acids, HCl, Lactobacillus acidophilus in intestine & vagina  Lysozyme: attacks cell wall of microorganisms & rendered it osmotically sensitive  Lactoferrin: present in human milk

JOYCE ANN S. MAGSAKAY

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BS MEDICAL LABORATORY SCIENCE

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OLFU VALENZUELA

IMMUNOOGY & SEROLOGY

IMMUNITY 2. INTERNAL DEFENSE MECHANISM - includes both cells and soluble factors play essential parts designed to recognize molecules that are unique to infectious organisms a. PHYSIOLOGIC FACTORS  Body temperature  Oxygen tension  Hormonal balance b. BASIC POLYPEPTIDES  SPERMIN: pH dependent polyamine found in semen & inhibits growth of g(+) bacteria  DEFENSIN: catanionic proteins present in human neutrophil that kill microbes by interacting with microbial membrane to form channels through which important metabolites escape c. INTERFERONS - group of molecules that limit the spread of viral Infections by blocking translation of viral CHONS  Alpha IFN: produced in WBC infected with virus  Beta IFN: produced in fibroblast infected with virus  Gamma IFN: produced in T-cytotoxic cells infected with virus d. COMPLEMENT - principal soluble mediator of inflammatory response e. ACUTE-PHASE PROTEINS:  C-Reactive Protein  Mannose Binding Protein  Haptoglobin  Fibrinogen  Ceruloplasmin  Serum Amyloid-A  Alpha-1-Antitrypsin  Apha-1-Acid Glycoprotein  Engogenous pyrogens f. CELLULAR DEFENSE MECHANISM  Neutrophils  Basophils  Eosinophils  Monocytes/Macrophages  Mast cells  Dendritic cells II. ACQUIRED / ADAPTIVE IMMUNITY (SPECIFIC) - not active until there is an invasion of microorganism - a reaction resulting from the invasion of a foreign substance - has greater response to secondary infection/exposure (with memory cells) TWO TYPES OF ADAPTIVE IMMUNITY: 1. ACTIVE IMMUNITY: produces his own antibody a. NATURAL ACTIVE: antigens enter the body naturally during infections & diseases b. ARTIFICIAL ACTIVE: antigens (Ag) are introduced in vaccines

JOYCE ANN S. MAGSAKAY

|

BS MEDICAL LABORATORY SCIENCE

|

OLFU VALENZUELA

IMMUNOOGY & SEROLOGY

IMMUNITY 2. PASSIVE IMMUNITY: receives antigen from others a. NATURAL PASSIVE: antibodies pass from mother to fetus via placenta or via colostrum on mother’s milk TWO ARMS OF ADAPTIVE IMMUNITY HUMORAL CELL-MEDIATED MECHANISM Antibody mediated Cell mediated CELL TYPE B-Lymphocytes T-Lymphocytes MODE OF Antibodies in biologic fluid Direct cell-to-cell contact ACTION Defense against viral & fungal infections, intracellular Primary defense against bacterial FUNCTION infections organisms, tumor antigens, & graft infection, parasites NATURE OF INFECTING Circulating Extracellular antigen Intracellular organism ANTIGEN Chronic, granulomatous infection, neoplasm, fungal, TYPE OF Acute pyogenic infection parasitic disease INFECTION VARIANTS

Ab-mediated hypersensitivities, Autoimmunity

Contact sensitivity, DTH, Allograft rejection, GVH response, elimination of tumors, formation of chronic granulomas

b. ARTIFICIAL PASSIVE: antibodies (Ab) are introduced by vaccines

JOYCE ANN S. MAGSAKAY

|

BS MEDICAL LABORATORY SCIENCE

|

OLFU VALENZUELA...